Method for carbon nanotube emitter surface treatment

ABSTRACT

The invention relates to a method for carbon nanotube emitter surface treatment, which is used to increase the number of carbon nanotube exposed on the triode structure device. For advancing the current density and magnitude of CNT emitter, the invention uses a method of casting surface treatment on the CNT emitter including the steps of coating an adhesive material on the surface of device; heating the adhesive material for adhibitting the surface; and lifting the adhesive material off.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates to a method for carbon nanotube emittersurface treatment, which is used to increase the number of CNT (carbonnanotube) exposed on device for advancing the current density andmagnitude of CNT emitter.

[0003] 2. Description of the Prior Art

[0004] To implement the possibility of displays planarization, theCNT-FED (carbon nanotube field emission) adopts the technology ofscreen-printing process and FED display in the prior art. It not onlykeep the image quality of CRT displayer, but also the advantage ofpower-saving and slim-volume, and with the characters of CNT includinglow-conducting electronic field required, high density of emissioncurrent, high stability, so it may offer a flat displayer with goodluminous efficiency, and large-size screen with power-saving andlow-cost.

[0005] Refer to FIG. 1, which is showing the luminous theory of thetriode structure of carbon nanotube field emitter display (CNT-FED) inthe prior art. That is a kind of regular structure, which is used toraise the electronic energy up, advance the luminous efficiency, anddiminish the control voltage. Wherein, the structure of CNT-FED luminoustheory including the processing steps of fabricating a cathode plate 102above a substrate 101, and further depositing the nano-scale carbonnanotube on the cathode plate 102, that is a electronic source 103. Thecathode plate 102 connects with a gate 105 by a dielectric 104, avoltage generated from the gate 105 is used to pull the electronics outof the cathode plate 102. the current direction of the electronics fromcathode plate 102 is as the directions of arrows on FIG. 1. Then,because of an anode plate 107 set on the triode structure, theelectronics emit from cathode plate 102 and impact on fluorescent screen106. Finally, it generates the red, green and blue light through a glassplate 108.

[0006] In the prior art, when manufacturing the CNT emitter, the CNT(Carbon Nano Tube) and the organic matters are mixed to produce the CNTpaste to be coated on the substrate and performed with masking by usingthe screen printing technology so as to form a field emissionelectronics source. Therefore, the number of the CNTs exposed on thesurface of the CNT layer is closely relative to the density of the fieldemission current. It will be the key point to affect the current densityof the field emission display. However, the drawback of the prior art isthe problem of the uniformity of the field emission electronics source.

[0007] In order to resolve the problem of the uniformity of the surfaceof the CNT layer of the CNT emitter in the prior art, the SamsungElectronic Inc. provides the relative technology where the laserscanning method is used for evening the surface. In U.S. Pat. No.6,436,221, assigned to the Industrial Technology Research Institute(ITRI) based in Taiwan and titled with “Method of Improving FieldEmission Efficiency for Fabricating Carbon Nanotube Field Emitters,” themanufacturing process for improving the field emission efficiency of theCNT electronics source is provided.

[0008] The casting surface treatment of the present invention canprocess the CNT electronics source in the triode or any structure andimprove the uniformity of surface of CNT on carbon nanotube fieldemitter display in any kind of structure, and then increase the numberof the CNT exposed on device.

SUMMARY OF THE INVENTION

[0009] It is a primary object of the present invention to provide amethod for carbon nanotube emitter surface treatment, which is used toincrease the number of carbon nanotube exposed on the triode structuredevice. For advancing the current density and intensity of CNT emitter,the invention uses a method of casting surface treatment on the CNTemitter including the steps of coating an adhesive material on thesurface of device; heating the adhesive material for adhibitting thesurface; and lifting the adhesive material off.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The objects, spirits and advantages of the preferred embodimentsof the present invention will be readily understood by the accompanyingdrawings and detailed descriptions, wherein:

[0011]FIG. 1 is a schematic diagram showing the luminous theory of thetriode structure of carbon nanotube field emitter display;

[0012]FIG. 2A is the 1st schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the firstpreferred embodiment of the present invention;

[0013]FIG. 2B is the 2nd schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the firstpreferred embodiment of the present invention;

[0014]FIG. 2C is the 3rd schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the firstpreferred embodiment of the present invention;

[0015]FIG. 3A is the 1st schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the secondpreferred embodiment of the present invention;

[0016]FIG. 3B is the 2nd schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the secondpreferred embodiment of the present invention;

[0017]FIG. 3C is the 3rd schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the secondpreferred embodiment of the present invention;

[0018]FIG. 3D is the 4th schematic diagram showing the method for carbonnanotube emitter surface treatment in accordance with the secondpreferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0019] In the triode structure of carbon nanotube field emission display(CNT-FED), the invention adopts a method for casting surface treatmentto increase the number of carbon nanotube exposed on the surface of thedevice. And the invention also can advance the current density andintensity of CNT emitter in gate hole formed around the CNT electronicsource in the triode or any structure of CNT-FED, then the CNT emittercan emit the electronics in high-density and great-intensity uniformly.

[0020] The method of surface treatment comprises the steps below:

[0021] Please refer to FIG. 2A to FIG. 2C, which are schematic diagramsshowing the method for carbon nanotube emitter surface treatment inaccordance with the first preferred embodiment of the present invention.There is showing a triode structure of CNT-FED using the manufacturingprocess of semi-conductor thin film. First, refer to the FIG. 2A, thereis a two-dimension distribution cathode plate 203 fabricating on a glasssubstrate 201, and there is a dielectric 205 between the glass substrate201 and a gate 207 of the triode CNT-FED. When there exists electriccharges on the gate 207, some free electronics will be pull out from thecathode plate 203. Then these free electronics will move to the way togate 207, and become a electronic channel. Furthermore, there are carbonnanotubes depositing above the cathode plate 203, and generating agreater current density, more powerful intensity CNT electronics source209.

[0022] In FIG. 2A, there is a dispenser 211, and coating an adhesivematerial 213 on the surface of the CNT-FED structure. The method of theinvention doesn't limited by the area size to be coated, and theadhesive material 213 is not only sticky but impervious to the device,that could be a thermal adhesives or a soluble material. Refer to FIG.2B, that is showing a step of melt of adhesive material 213, as theadhesive material 213 is heated, then it will be soften and attached onthe triode structure surface of CNT-FED closely and uniformly. After theprocess of coating the adhesive material 213 and melt to attach thesurface of device, next, lifting the adhesive material 213 off from thesurface of CNT-FED, especially from the surface of CNT electronic source209 above that device as showed in FIG. 2C. For improving the luminosityand uniformly display of panel as the electronics impact the fluorescentscreen on anode plate, the step of lifting material off can remove theimpurity, which affects the electronics emission, from the surface ofCNT, and increase the number of carbon nanotube exposed on the triodestructure device.

[0023] The FIG. 3A to FIG. 3D are the schematic diagrams showing themethod for carbon nanotube emitter surface treatment in accordance withthe second preferred embodiment of the present invention. In thesediagrams, there is cathode plate 303 fabricating on a substrate 301, andthere is a dielectric layer 305 deposited between a cathode plate 303and the gate 307 of the triode CNT-FED. Furthermore, there is a CNTlayer 309 deposited carbon nanotube electronic source and is set betweenthe cathode plate and the gates existed in said triode structure,wherein the CNT layer 309 mentioned above is the CNT electronics source309.

[0024] In FIG. 3A, which is showing the step of coating an activator 311on the surface of the CNT-FED triode structure, the activator 311 couldbe an interface activator or any release agent, and the activator 311 isused to prevent too close sticky between the adhesive material 313 anddielectric layer 305 in the gate hole. Next, refer to FIG. 3B, which isthe step of coating an adhesive material 313 on the activator above theCNT-FED triode structure. The process showed on FIG. 3C is a step ofpressing the adhesive material 313 for adhibitting the device surfaceclosely by a laminator, otherwise, the adhesive material 313 could bethe thermal adhesives or a soluble material. Please refer to FIG. 3D,which is the step of lifting the adhesive material 313 off from thetriode surface of CNT-FED, i.e. lifting the impurity or any otheradhesion, which will affect the electronics emission density andintensity of CNT electronics source 309, off from the device surface.

[0025] A method for carbon nanotube emitter surface treatment, which isused on a carbon nanotube electronics source for increasing the numberof carbon nanotube exposed on a triode or any structure of CNT-FED, thenthe method can advance the current density and intensity of CNT emitter,the method for carbon nanotube emitter surface treatment comprising thesteps of:

[0026] According to the above discussion, the present inventiondiscloses method for carbon nanotube emitter surface treatment, whichadopts a method of casting surface treatment on the CNT emitter used toincrease the number of carbon nanotube exposed on the triode structuredevice, and then advancing the current density and intensity of CNTemitter.

[0027] Although this invention has been disclosed and illustrated withreference to particular embodiments, the principles involved aresusceptible for use in numerous other embodiments that will be apparentto persons skilled in the art. This invention is, therefore, to belimited only as indicated by the scope of the appended claims.

What is claimed is:
 1. A method for carbon nanotube emitter surfacetreatment, which is used on a carbon nanotube electronics source forincreasing the number of carbon nanotube exposed on a triode or anystructure of CNT-FED, then the method can advance the current densityand intensity of CNT emitter, the method for carbon nanotube emittersurface treatment comprising the steps of: coating an adhesive materialon the surface of said CNT-FED; heating said adhesive material foradhibitting the surface; and lifting said adhesive material off.
 2. Themethod for carbon nanotube emitter surface treatment as recited claim 1,wherein said adhesive material is a hot melt glue or a soluble material,organic material, inorganic material and strippable material.
 3. Themethod for carbon nanotube emitter surface treatment as recited claim 1,wherein said adhesive material sticks on said carbon nanotubeelectronics source.
 4. The method for carbon nanotube emitter surfacetreatment as recited claim 3, wherein said carbon nanotube electronicsource is set between a cathode plate and a gate existed in said triodestructure.
 5. A method for carbon nanotube emitter surface treatment,which is used on a carbon nanotube electronics source for increasing thenumber of carbon nanotube exposed on a triode or any structure ofCNT-FED, then the method can advance the current density and intensityof CNT emitter, the method for carbon nanotube emitter surface treatmentcomprising the steps of: coating an activator on the surface of saidCNT-FED; coating an adhesive material on said activator; pressing saidadhesive material for adhibitting the surface; and lifting said adhesivematerial off.
 6. The method for carbon nanotube emitter surfacetreatment as recited claim 5, wherein said activator is an interfaceactivator surfactant or a release agent.
 7. The method for carbonnanotube emitter surface treatment as recited claim 5, wherein saidadhesive material is a hot melt glue or a soluble material, organicmaterial, inorganic material and strippable material.
 8. The method forcarbon nanotube emitter surface treatment as recited claim 5, whereinsaid step of pressing said adhesive material for adhibitting the surfaceis achieved by a pressing machine.
 9. The method for carbon nanotubeemitter surface treatment as recited claim 5, wherein said adhesivematerial sticks on said carbon nanotube electronics source.
 10. Themethod for carbon nanotube emitter surface treatment as recited claim 9,wherein said carbon nanotube electronic source is set between a cathodeplate and a gate existed in said triode structure.